Maintower is a 200 metre (656 foot) skyscraper in Frankfurt am Main, Germany. It is named after the river Main. A 40 metre (131 foot) communications tower is mounted atop the building. It features five underground floors, as well as two public viewing platforms. The tower currently remains the only skyscraper in Frankfurt with a public viewing observatory. It is currently the 4th tallest building in Frankfurt.
Maintower was built between 1996 and 1999 and contains the Landesbank of Hesse and Thuringia (Helaba), the German Office of Merrill Lynch and a television studio of the Hessischer Rundfunk, among other enterprises. The first tenants moved in November 5, 1999, and the official inauguration was January 28, 2000. During weather reports by the television station, the weather reporter stands on the top of the building.
The foyer of the building has two art pieces accessible to the public: the video installation by Bill Viola "The World of Appearances" and the wall mosaic by Stephan Huber "Frankfurter Treppe / XX. Jahrhundert" (Translation: "Frankfurt's Steps/20th Century")
The tower's design features what appears to be two connected towers. The smaller of the two is of a cuboid shape and a design common to 1970s architecture. The second and taller of the two towers is a circular tower with an entire blue glass exterior which features the transmission tower on top.